The present invention relates to an optical member driving device which drives a lens or the like.
In the U.S. Pat. No. 5,986,826, it is described an optical member driving device having a piezoelectric element as a power source and a movable member frictionally engaging with a driving friction member which is reciprocated in an axial direction of the driving friction member, wherein the movable member is formed integrally with a frame member holding the lens.
Furthermore, an another example of the driving device in which the driving friction member is reciprocated in the axial direction by a piezoelectric element is described for instance, in Japanese unexamined patent publication No. 2004-80964.
Conventionally, the movable member is formed by an injection molding process and dose not have enough hardness of an engaging surface abutting on the driving friction member, therefore the movable member should be reinforced by placing the metal member or coating some metal onto the engaging surface as described in the U.S. Pat. No. 5,986,956.